Rei Reiho joins the player's party after completion of the Library dungeon. She has the option of calling upon the power of one of three deities at the shrine at Mt. Kasagi. This affects her spell list. The deities are Amaterasu, Gabriel, and Ishtar. Amaterasu is focused more on offensive magic, Gabriel on support magic, and Ishtar on recovery magic.
Rei obtains the top three skills upon selecting her deity. Skills are learned from top to bottom. The amount of spells that Rei knows is determined after leveling up using the following formula with the decimals truncated:[1]
While not in her natural learnset, she can also learn the skill Shuffler through an event.